|Publication number||US6867394 B2|
|Application number||US 10/617,094|
|Publication date||Mar 15, 2005|
|Filing date||Jul 11, 2003|
|Priority date||Oct 5, 2001|
|Also published as||US20040007564|
|Publication number||10617094, 617094, US 6867394 B2, US 6867394B2, US-B2-6867394, US6867394 B2, US6867394B2|
|Inventors||George T. C. Li|
|Original Assignee||George T. C. Li|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (9), Referenced by (13), Classifications (20), Legal Events (6)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application is a continuation-in-part of U.S. patent application Ser. No. 10/302,202 entitled Roasting Oven with Dual Heating Elements filed Nov. 22, 2002, now U.S. Pat. No. 6,686,569, which is a continuation-in-part of U.S. patent application Ser. No. 09/971,286, now U.S. Pat. No. 6,509,550 entitled Roasting Oven with Dual Heating Elements filed Oct. 5, 2001 and claims the benefits provided under 35 USC § 120.
The present invention relates to cooking appliances and, more particularly, to a large capacity, roasting oven including a food serving system. In one embodiment the roasting oven includes a wrap-around type heating element for applying heat to the cooking vessel and a top heater element for browning. In an alternative embodiment the top heater element is omitted to simplify manufacturing and to reduce the cost to the consumer.
Electric cooking pots for preparing and serving hot foods are well known to those skilled in the art. Such electric cooking pots typically include a heating element arranged in functional relation underneath the bottom surface of the cooking well for supplying heat. Such cooking wells are often constructed of stainless steel or enameled steel for reasons of durability and sanitation. However, it is known that both stainless steel and enameled steel have relatively low coefficients of heat conductivity as compared with other metals.
This presents a particular problem for cooking vessels of large capacity (i.e. up to 26 quarts). Applying heat only to the bottom surface of such a large capacity cooking vessel, especially when constructed of stainless steel or enameled steel, can result in the upper portion of the cooking vessel being insufficiently heated. Thus, the food in the upper portion of the cooking vessel may become too cool for serving purposes due to the loss of heat in combination with the low rate of heat conductivity and the slow rate at which heat is supplied to the upper portion of the cooking vessel.
The heat distribution problem is compounded in a roasting oven of large capacity and cannot be resolved by simply increasing the power output of the heating element. This is due to the fact that the increased heater output tends to overheat and to cause malfunction of the temperature control components and electronic circuitry, which are typically contained within the oven housing. Thus, the present roasting oven has been developed to solve these problems and other shortcomings of the prior art.
Numerous examples of deep well cookers are available in the prior art and their discussion follows. One example of a prior art deep well cooker is disclosed in U.S. Pat. No. 4,024,377 to Henke comprising a heat sink preferably formed of aluminum or another corrosion resistant metal having a relatively high coefficient of heat conductivity, which is positioned over the deep well member from below. The heat sink member is generally U-shaped and has a bottom part parallel to and spaced from the bottom of the well member and side parts parallel to and engaging the sides of the well member in heat exchanging relation. An electric heating element is disposed in the space between the bottom of the well member and the bottom part of the U-shaped heat sink member. When the electric heater is energized, heat is supplied to the bottom of the well member by direct radiation and by radiation from the bottom part of the U-shaped member and by convection due to the air in the space occupied by the heating element. Simultaneously, however, heat also flows from the bottom part of the U-shaped member, up side parts of the U-shaped member, and into the sides of the well member. The heat supplied by conduction to the sides of the well member provides for more uniform heating of the well member while also providing for more efficient utilization of the energy supplied to the heating element. However, this device is designed for use with a deep well cooker having a capacity of approximately 8-12 quarts based on the dimensions provided in the specifications. This device necessarily becomes less efficient when applied to a larger capacity cooker having increased side wall dimensions.
Another example of a prior art cooking device having multiple heating elements is disclosed in U.S. Pat. No. 3,393,295 to Jepson et. al. comprising a pan with a lower electric heating element supported on its underside and a deep cover with an upper heating element supported within. A thermostatic control is connected to the lower heating element for energization thereof. When the cover is closed, an electrical connection for energizing the upper heating element is completed. The control serves thermostatically to control the energization of either element in a repeating, alternating sequence and is capable of performing the functions of a frying pan, broiler, and oven. However, this invention is not directly applicable to deep well cookers nor does it disclose a wrap-around heating element for controlling heat distribution to the upper surfaces of a deep well member within such a cooker.
U.S. Pat. No. 2,265,295 to Layton discloses an electric roaster with a housing and a well with a bare resistance wire wrapped around asbestos paper which serves as an insulator (see FIGS. 1-2). Layton does not disclose or suggest control circuitry allowing various cooking modes.
U.S. Pat. No. 2,292,854 to Wilcox discloses an electric heating wire wrapped around a mica support strip with notches and sandwiched between insulating layers (see FIG. 3). Wilcox also discloses a spring clamp (see FIG. 6) and rivet fastening of laminated structures.
U.S. Pat. No. 6,170,388 to Shovick; U.S. Pat. No. 2,187,888 to Nachumsohn; and German Patent document 3606800 to Rederer disclose heating/cooking devices, which are pertinent to applicant's disclosure in the present application.
Accordingly, the present invention provides a roasting oven including a food serving system having a large capacity (i.e. up to 26 quarts) that includes a wrap-around heating element, which is disposed about the heating well for heating the sides thereof, and a top heating element for browning (i.e. to scorch slightly in cooking) mounted within the oven lid. In another embodiment the top heating element is omitted to simplify manufacturing and to reduce cost to the consumer.
Both the wrap-around heating element and the top heating element are provided in alternative embodiments utilizing different types of heating elements for versatility in manufacturing and heating requirements. The wrap-around heating element and the top heating element are interconnected by temperature controls for heat regulation and a function control switch for selectively energizing the desired heating elements individually or in combination.
For convenience the roasting oven lid containing the top heating element is removable being provided with detachable electrical connectors, which form a portion of the electrical circuit for the top heating element. The present roasting oven also includes serving containers for maintaining the cooked food in ready-to-eat condition and for re-heating leftover food items.
Other features and technical advantages of the present invention will become apparent from a study of the following description and the accompanying drawings.
The novel features of the present invention are set forth in the appended claims. The invention itself, however, as well as other features and advantages thereof will be best understood by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying figures wherein:
With further reference to the drawings, there is shown therein an embodiment of a roasting oven in accordance with the present invention, indicated generally at 10, and illustrated in FIG. 1A. The present roasting oven 10 is comprised of an outer housing 22 equipped with fixed external handles 24 and feet 26. The roasting oven 10 is also provided with a lid 28 equipped with a handle 30.
In an alternative constructon, the roasting oven 10 is provided with folding handle assemblies, indicated generally at 24′, as shown in
In the preferred embodiment the housing 22 is constructed of sheet steel, heat resistant plastic, or other suitable material and is provided in various exterior finishes such as powder coating, stainless steel, or plated steel.
The present roasting oven 10 also includes an internal heating well 36 disposed within the housing 22 as more clearly shown in
The present roasting oven 10 also includes a removable cooking liner 45 including a peripheral flange member 45 a which is seated on the upper edge of the housing 22 as shown. The liner 45 is constructed of stainless steel, enamel-coated steel, cast aluminum, ceramic, or other suitable material. The cooking liner 45 is easily removed from the heating well 36 for cleaning for the convenience of the user.
A layer of heat-resistant insulating material (not shown) is disposed in the air space as at 20 between the housing 22 and the cooking well 36 as shown in
Referring to an embodiment illustrated in
Referring again to
In the embodiment shown in
As more clearly shown in
Referring now to
The present roasting oven 10 is designed for use with standard household electrical systems. In the preferred embodiment the wrap-around heating element 40 is designed to operate in the range of 1000-1500 watts and the top heating element 150 to operate in the range of 25 to 150 watts. This wattage rating can be varied for a given application and capacity of the oven.
With reference to
Still referring to
Using an alternative construction technique shown in
In this manner, it will be understood that a single-sided heater element having at least 75% of the total amount of heater wire 53 used in its construction disposed on one surface of the sheet 70 may be produced. Such a single-sided heating element (
In both of the above described embodiments, the sheet 70 is permanently captured between the interior and exterior sheets 72 and 74, and secured at periodic intervals as shown by rivets 75 or other suitable fasteners to maintain alignment of the individual layers.
Various alternative materials and techniques may be employed in the fabrication of the heating elements as shown in
In another embodiment shown in
In yet another embodiment shown in
Referring now to
In an alternative construction of the heater lead wire assembly, indicated generally at 50′, in
In the embodiment shown in
The wiring is disposed within a wire channel 92 formed in the body 101 of the hinge and extends through the hinge mechanism, indicated generally at 100, to a power cord 104, which extends from the housing 22 as shown. An electrical circuit for the top heating element 150 is completed at contact 102 when the hinge mechanism 100 is in the closed position as shown in
In another embodiment shown in
Plug connector 155′ is received in an electrical receptacle 157′, which includes a permanent magnet block 159. Magnet block 159 engages and retains plug connector 155′ at the interface thereof to maintain electrical contact with the top browning element 150′ and to secure the lid 28 in position on the oven. The plug connector 155′ and receptacle 157′ may be conveniently disconnected for food service, cleaning, and storage purposes.
In an assembly procedure of the present roasting oven 10, the wrap-around heating element 40 is secured to an outer surface of the heating well 36 by use of an adjustable band clamp, indicated generally at 83, as shown in FIG. 9. The band clamp 83 is constructed of sheet metal such as steel in the form of an elongated belt and includes a turnbuckle mechanism, indicated generally at 82, which is capable of securing the heating element 40 about the outer periphery of the heating well 36. The wrap-around heating element 40 is mounted onto studs 77 (
A plurality of elongated slots 79 (
Referring again to
It will be appreciated that because the present invention omits the conventional bottom heating element of the prior art, the temperatures achieved on the undersurface of the heating well 36 and housing 22 in operation are relatively lower in comparison to prior art cookers. Accordingly, the roasting oven 10 includes a ventilated compartment 80 as shown in
The power supply circuit board 81 is mounted in space to-part relation to the undersurface of the housing 22 by the use of spacers 84 so as to create an air gap as at 85 to further isolate the circuit board 81 from the housing 22 and the heat source. In addition, a layer of mica insulation board or other suitable insulating material is installed as at 86 to further insulate and protect the power supply circuit board 81.
Still referring to
Referring now to
Referring now to
The housing 22′ is constructed of sheet steel, heat resistant plastic, or other suitable material and is provided in different exterior finishes such as powder coating, stainless steel, or plated steel.
The present roasting oven 10′ also includes an internal heating well 36′ disposed within the housing 22′ as more clearly shown in
The roasting oven 10′ also includes a removable cooking liner 45′ including a peripheral flange member 45 a′ which is seated on the upper edge of the housing 22′ as shown. The liner 45′ is constructed of stainless steel, enamel-coated steel, cast aluminum, ceramic, or other suitable material. The cooking liner 45′ is easily removed from the heating well 36′ for cleaning.
A layer of heat-resistant insulating material (not shown) is disposed in the air space as at 20′ between the housing 22′ and the cooking well 36′ as shown in
Referring again to
Referring now to
The present roasting oven 10′ is also designed for use with standard household electrical systems. In this embodiment the wrap-around heating element 40 is designed to operate in the range of 1000-1500 watts. Of course, this wattage rating may be varied for a given application and capacity of the oven. In this embodiment of the roaster oven 10′, the wrap-around heating element 40 is constructed in the same manner as described hereinabove and illustrated in
In summary, the present invention has been developed to provide a roasting oven having a large capacity (i.e. up to 26 quarts) that includes a flexible, wrap-around heating element which is disposed about the heating well for heating the sidewalls thereof and a top heating element for browning. In an alternative construction the top heating element is omitted to reduce manufacturing costs.
The wrap-around heating elements 40, 140 are provided in different configurations to facilitate manufacturing and heating. Both the wrap-around heating element 40 and top heating elements 150, 150′ are electrically interconnected to a temperature control panel featuring a push-button control film interface for selectively energizing the heating elements. The roasting oven may include a detachable lid member having a top browning element featuring quick connect/disconnect electrical connectors to enhance food service and cleaning. The present roasting oven may also include an exterior ventilated compartment for housing the power supply circuit board for insulating the same from the high heat source necessary for a roasting oven of this capacity.
The present roasting oven is also provided with a food serving set for maintaining food in ready-to-eat condition and for re-heating leftover food items. The food serving set is available in alternative configurations
Although not specifically illustrated in the drawings, it should be understood that additional equipment and structural components will be provided as necessary, and that all of the components described above are arranged and supported in an appropriate fashion to form a complete and operative roasting oven incorporating features of the present invention.
It is also understood that variations may be made in the present invention without departing from the scope of the invention. For example, the present roasting oven may utilize double-sided and also single-sided heater elements as disclosed herein, which may be advantageous for specific applications.
Moreover, although illustrative embodiments of the invention have been described, a latitude of modification, change, and substitution is intended in the foregoing disclosure, and in certain instances, some features of the invention will be employed without a corresponding use of other features. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention.
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|U.S. Classification||219/433, 219/542, 219/386, 219/402, 219/432, 219/541|
|International Classification||A47J36/06, A47J37/06, A47J27/00, H05B3/16|
|Cooperative Classification||A47J36/06, A47J27/004, A47J37/0629, H05B3/16, A47J37/0623|
|European Classification||H05B3/16, A47J27/00B, A47J37/06C, A47J36/06, A47J37/06C4|
|Feb 23, 2007||AS||Assignment|
Owner name: ACORNE ENTERPRISES, LLC, NEVADA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:LI, GEORGE T.C.;REEL/FRAME:018961/0658
Effective date: 20061228
|Sep 12, 2008||FPAY||Fee payment|
Year of fee payment: 4
|Sep 13, 2012||FPAY||Fee payment|
Year of fee payment: 8
|Oct 21, 2016||REMI||Maintenance fee reminder mailed|
|Mar 15, 2017||LAPS||Lapse for failure to pay maintenance fees|
|May 2, 2017||FP||Expired due to failure to pay maintenance fee|
Effective date: 20170315